This invention relates to material handling systems, and in particular, to a material handling system finding application in the handling of cast iron parts in foundries. While the system is described with particular reference to its foundry application, those skilled in the art will recognize the wider applicability of the inventive principles disclosed hereinafter.
Material handling in most foundries today can be best described as archaic. In general, sand molds are loaded with the molten material to form the desired molded product. After the parts are cast at a molding station, they are allowed to cool to a set condition and then removed from the molds. The cast parts or casting thereafter require some period for further cooling, conventionally in the vicinity of two to four hours before they can be handled by other foundry personnel. After cooling, the castings are transported to a suitable storage area where they are backlogged before further processing takes place. Generally, it is more efficient to maintain the molding machinery in continuous or nearly continuous operation. However, to accomplish this objective, present day foundries must backlog the molded or cast parts if molding machinery efficiency is to remain high. Consequently, foundries not employing our invention require a considerable floor area for part storage after casting. From storage, the parts are processed as needed through a cleaning machine which is known in the art as a shot blast machine or apparatus. The shot blast machine cleans the casting by an abrasion process. After general cleaning in the shot blast machine, the castings are moved to another finishing station where metal flashes are clipped away. Grinding is performed as needed, and various other operations are performed on the castings to obtain the final product. Movement of the castings between the various work stations in the past has been accomplished by stacking the castings in tote carts which are moved by conventional forklift trucks.
The presence of forklift trucks, particularly when they are gasoline powered, adds considerable noise and air pollution to the foundry. The grinding, chipping, and flash removal, for example, accomplished on the castings likewise contribute heavily to pollution within the foundry. Recently, foundry pollution and environmental working conditions have been the target of stringent regulations, and the invention disclosed hereinafter enables a foundry to meet these new requirements by eliminating a number of deficiencies found in prior foundry operation. First, our invention eliminates the need for forklift trucks for moving material by utilizing a suitable conveyor system to transport the material between the various work stations. Second, it employs an environmentally safe, enclosed finishing room where casting finishing work can be accomplished without disturbing the environment of the remaining foundry area. Third, it eliminates unnecessary foundry personnel by mechanizing many of the operations previously accomplished by hand, or simplifies the operation so fewer workers are required to accomplish the task. Fourth, it eliminates the need for a separate casting storage area by using a portion of the conveyor system employed in part transport as a storage medium.
One of the objects of this invention is to provide a continuous flow pattern for handling material.
Another object of this invention is to provide a continuous flow pattern for handling material, which is adapted for carrying cast parts, the system including an accumulator for permitting cooling of the parts after casting.
Another object of this invention is to provide a system for handling material which includes an environmentally acceptable finishing room for conducting operations on the parts.
Another object of this invention is to provide a finishing room where parts are fed into and from the finishing room in an expeditious manner.
Another object of this invention is to provide a system for handling material in which rejected parts may be conveyed to a storage area for later rework.
Yet another object of this invention is to provide a material handling system which eliminates or reduces the need for a separate storage area for castings prior to finishing work being accomplished on the castings.
Other objects of this invention will be apparent to those skilled in the art in light of the following description and accompanying drawings.